Apparatus for discharging static electricity

ABSTRACT

Apparatus is disclosed for use in conjunction with operators such as doorknobs, switches, pushbuttons and the like to enable a person to effect a painless discharge of an accumulated charge of electricity when the person contacts the operators. In each embodiment, the apparatus comprises two electrically conductive members one of which carries a contact surface which protrudes therefrom toward the other member but which is normally spaced therefrom by means of insulation including an airgap. Means is provided to bias the members away from one another so that the accumulated static charge is transferred from the person when he touches the member carrying the contact surface and urges it against the biasing means into engagement with or at least into proximity with the other member. The embodiments associated with doorknob structures are constructed to transfer static electricity when the knob is pushed, pulled or rotated; the embodiment associated with the pushbutton is constructed to transfer static electricity when the button is pushed; and the embodiment associated with the switch is constructed to operate when the switch is operated.

United States Patent [72] Inventor Stanley Backer 5 Irving Road, Waban,Mass. 02168 [21] Appl. No. 569 [22] Filed Jan. 5, 1970 [45] PatentedNov. 16, 1971 [54] APPARATUS FOR DISCHARGING STATIC ELECTRICITY 13Claims, 19 Drawing Figs. [52] US. Cl ZOO/61.58, 317/2 R [51] Int.ClH01h3/l6 [50] Field of Search ZOO/61.58. 157,169 PB, 172 A; 317/2 R;174/5 R, 5.1, 5.2 [56] References Cited UNITED STATES PATENTS 559,4165/1896 Soper 200/172 X 2,038,323 4/1936 Thomas 200/61.58 3,462,! 838/1969 Dudley et a1 317/2 R X ABSTRACT: Apparatus is disclosed for usein conjunction with operators such as doorknobs, switches, pushbuttonsand the like to enable a person to effect a painless discharge of anaccumulated charge of electricity when the person contacts theoperators. in each embodiment the apparatus comprises two electricallyconductive members one of which carries a contact surface whichprotrudes therefrom toward the other member but which is normally spacedtherefrom by means of insulation including an airgap. Means is providedto bias the members away from one another so that the accumulated staticcharge is transferred from the person when he touches the membercarrying the contact surface and urges it against the biasing means intoengagement with or at least into proximity with the other member. Theembodiments associated with doorknob structures are constructed totransfer static electricity when the knob is pushed, pulled or rotated;the embodiment associated with the pushbutton is constructed to transferstatic electricity when the button is pushed; and the embodimentassociated with the switch is constructed to operate when the switch isoperated.

PATENTEnuuv 1s |97l 3.621.164

sum 3 or 3 FIGIS.

INVENTORZ STANLEY BACKER BY Wan d Warz AT TYS.

APPARATUS FOR DISCI-IARGING STATIC ELECTRICITY The present inventionrelates to apparatus for discharging static electricity, and moreparticularly, the present invention relates to apparatus for enabling aperson to effect a painless discharge of static electricity whenoperating such things as metallic doorknobs, electrical toggle switches,pushbuttons, or the like.

It is well-known that a charge of static electricity may be generated bya person walking across a floor covered by carpeting of certainsynthetic materials or when wearing clothing manufactured from certainsynthetic fibers. Under conditions of low-relative humidity, arelatively large electrical potential may be developed. When the personextends his fingers or hand while attempting to touch an object at alower electrical potential, current flows from the extremities thereof,causing the person to feel a shocking sensation. Thus, at present, theperformance of ordinary acts such as grasping a metallic doorknob on adoor, touching the metal plate on a toggle switch or depressing ametallic pushbutton often causes people considerable annoyance anddiscomfort.

In an efiort to obviate the foregoing disadvantages, some carpetmanufacturers provide metal ground wires in their synthetic carpets.This approach to the problem has not been satisfactory, however, becauseit has not been entirely effective. In addition, synthetic carpetinghaving metal ground wires is expensive to manufacture. Insulators, suchas rubber covers, have also been installed on doorknobs and the like inanother attempt to solve the shock problem. However, the use of suchdevices only postpones the shock which a person ultimately receives whentouching a metallic object at an electrical potential lower thanhimself.

In view of the foregoing, it is the primary object of the presentinvention to provide novel apparatus for enabling a person to painlesslydischarge an accumulated charge of static electricity. V

It is another object of the present invention to provide simple andinexpensive apparatus for use in conjunction with doorknobs, toggleswitches, pushbuttons and like structures to enable a person to operatethese devices without receiving an electrical shock after walking acrossa floor covered by carpeting of certain synthetic materials or whenwearing clothing manufactured from certain synthetic fibers.

As a further object, the present invention provides improved doorknobstructures which operate to discharge static electricity when manuallyengaged by a person and either pushed, pulled or rotated to actuate thelatching assembly connected thereto.

It is a still further object of the present invention to provide uniqueapparatus for use on a conventional doorknob to enable a person toeffect a painless discharge of static electricity when gripping theknob.

As another object, the present invention provides a unique cap forattachment to a conventional pushbutton to automatically effect adischarge of static electricity from a person when the button isdepressed.

A still further object of the present invention is to provide a novelmetallic element associated with a wall-type toggle switch fordischarging static electricity from a person when the switch isoperated.

The present invention also has as an object the provision of dischargeapparatus to enable a person to periodically effect a positive andcomplete discharge of static electricity.

More specifically, each embodiment of the discharge apparatus of thepresent invention comprises first and second electrically conductivemembers disposed in normally spaced apart relation with one of themembers carrying contact means protruding therefrom toward the other.Insulation means, including an airgap, is provided between the members;and means, including a resilient insulator, is provided to bias themembers away from one another to effect the required spacing. Staticelectricity is painlessly transferred from a person and to the firstmember when the person engages the second member and displaces itagainst its bias toward the first member and into engagement therewithor at least sufficiently close thereto to cause the static electricityto jump from the second member to the first member.

In the embodiments of the invention preferred for use with doorknobs,the first and second members are formed integrally with a doorknobstructure and in other embodiments the first member is a doorknob andthe second member is a removable device carried thereon, the apparatusof these embodiments operating to discharge static electricity when theknob is pulled, pushed, rotated or squeezed.

In the embodiments preferred for use with switches, the first member isa metallic receptacle mounting a cover through which the handle of atoggle switch projects and the second member is a spring element mountedon the front of the cover' to discharge static electricity when thespring element is urged against the cover and the switch is operated. Ina further em bodiment, the first member includes a metallic plateslidably mounting a pushbutton and the second member includes a capsurrounding terminus of the button and insulated therefrom, the caphaving an annular surface confronting the plate a spaced distancetherefrom and being operable to transfer static electricity to the platewhen the button is depressed and the surface engages the plate.

These and other objects, features and advantages of the presentinvention should become apparent from the following description whentaken in conjunction with the accompanying drawings in which:

FIGS. 1, 3 and 5 are partially sectioned side elevational views of threedifferent doorknob structures embodying the present invention;

FIGS. 2, 4 and 6 are sectional views taken along lines 2-2, 4-4 and 6-6of FIGS. 1, 3 and 5 respectively;

FIG. 7 is a partially sectioned, side elevational view of a conventionaldoorknob mounting removable apparatus embodying the present invention;

FIG. 8 is a fragmentary sectional view taken along line 8-8 of FIG. 7;

FIGS. 9 and 10 are fragmentary sectional views of the apparatus of FIG.7 illustrating portions thereof in operating positions;

FIG. 11 is a partially sectioned, side elevational view of aconventional doorknob mounting removable squeeze-type dischargeapparatus embodying the present invention;

FIG. 12 is a sectional view taken along line 12-12 of FIG. 1 1;

FIG. 13 is an inverted plan view of the knob of FIG. 11;

FIG. 14 is a sectional view of a pushbutton mounting discharge apparatusembodying the present invention;

FIG. 15 is a partially sectioned, side elevational view of an electricaltoggle switch mounting discharge apparatus embodying the presentinvention;

FIG. 16 is a front elevational view of the apparatus illustrated in FIG.15;

FIG. 17 is a view similar to FIG. 15 but illustrating the dischargeapparatus in one of its operating positions for transferring staticelectricity;

FIG. 18 is a detached perspective view illustrating the underside of theapparatus of FIGS. 15-17; and

FIG. 19 is an enlarged fragmentary sectional view of the upper end ofthe discharge apparatus illustrated in FIGS. 15-17.

Referring now to the drawings, there are disclosed in FIGS. 1-6(Sheet 1) doorknob structures 10, 30 and 60 embodying the presentinvention. The structure of FIGS. 1 and 2 operates to discharge staticelectricity when the knob 10 is pulled rearwardly or displacedrightward; the structure of FIGS. 3 and 4 operates to discharge staticelectricity when the knob 30 is pushed forwardly or displaced leftward;and the structure of FIGS. 5 and 6 operates to discharge staticelectricity when the knob 50 is rotated in the clockwise orcounterclockwise directions. Common to each of the aforementioneddoorknob structures is a first member or shank, ll 31 and 51 rotatablein a collar 12, 32 and 52 comprising part of a latching assembly 13, 33and 53 mounted in a door 14, 34 and 54 respectively and being operableupon rotation of the shank. A second member or hollow knob 15, 35 and 55surrounds the terminal portions of the respective shanks and isoperable, in a manner to be described, to discharge static electricity,and actuate the respective latching assemblies.

As noted heretofore, it is well-known that during periods oflow-relative humidity a person may accumulate a charge of staticelectricity by walking across a floor covered with certain syntheticcarpeting materials or when wearing clothing made from certain syntheticfabrics. Thereafter, when extending his fingers to turn a doorknob, todepress an elevator call button, to operate a toggle switch, or toactuate like devices, an arc of electricity may jump from the extremityof his fingers and to the device, causing the sensation of electricshock to be felt. The magnitude of the shock, of course, depends on thequantity of charge generated and the potential difference between theperson and the device, with well-grounded objects such as doorknobs onmetal doors, metallic switch cover plates causing substantial discomfortwhen touched.

The foregoing disadvantages are obviated by the present invention which,in accordance with its primary object, provides apparatus for use inconjunction with the aforementioned and like devices to enable a personto touch and operate the devices without receiving an electrical shock.To this end, the first and second members, i.e., the shank 11 and knobin the FIG. 1 embodiment is spaced apart by means of insulation whichprovides a normally interrupted electron flow path between the knob 15and the shank 11 but which provides a completed flow path when the knobis pulled. In addition, the knob 15 is mounted onto its shank 11 in amanner which causes the latching assembly 13 to be actuated when theknob 15 is rotated on its axis A in either the clockwise orcounterclockwise directions. For these purposes, the insulation meanscomprises a faceted molded insulator 16 mounted in the terminal end ofthe shank 11, a band of insulation 17 on the periphery of the shankadjacent its terminus, and an airgap 18 surrounding the bank 17 and theend of the shank 11. The knob 15 is mounted for axial displacementforwardly and rearwardly on the shank 11 by means of a forwardlyprotruding stem 15' which is slidably received in an axial bore locatedcentrally in the insulator 16. Means is also provided to couple the knob15 to the shank 11 to prevent relative rotation therebetween. In thepresent instance, the coupling means comprises three elongated catches19,19 mounted in rearwardly opening cavities in the shank 11 whichregister with a like number of forwardly opening cavities in the knob15. The catches 19,19 extend axially a spaced distance outwardly fromthe axis A, and the cavities in the knob 15 threadedly mount set screws20,20 which may be rotated, as will be more fully described hereinafter,to vary the airgap 18. Thus, with this structure, rotation of the knob15 causes the shank l1 and the latching assembly 13 to operate throughthe interengagement of the catches 19,19.

In order to complete the electron flow path when the knob 15 is pulledrearwardly or displaced rightward, contact means is provided on the knob15 and the shank 11. As may be seen in FIGS. 1 and 2, the contact meanscomprises forwardly facing arcuate surfaces 21,21 on circumferentiallyinterrupted flanges 11a, Ila extending radially outward on the terminusof the shank l1 and a like number of circumferentially interruptedrearwardly facing arcuate surfaces 150, 15a in registry therewith on theknob 15. Each surface 15a has a raised portion tapering toward an apex15b which confronts the surface on the flange 11a and engages it whenthe knob is pulled. The surfaces are interrupted to enable the knob 15to be mounted on its shank 11 by aligning the interruptions on the knobwith the flanges 11a, 11a on the shank 11, displacing the knob axially,and then rotating the knob to cause the surfaces to register with oneanother.

For the purpose of normally maintaining the airgap l8 the apexes 15b,15b from the surface of the flanges 11a, 110. Also, means is provided tolimit the airgap l8 and to adjust the applied biasing force. In theembodiment of FIG. 1, the biasing means comprises a compression spring23 engaged between an annular shoulder 24 in an axial recess in the knob15 and the head 25 of a threaded fastener 26 threaded into the insulator16. In the present instance, the threaded fastener 26 is a bolt which isoperable upon rotation in the clockwise direction (FIG. 2) to compressthe spring 23 and increase the pulling force required to interengage thecontact surfaces and operable upon rotation in the counterclockwisedirection to relieve the compression of the spring 23 and reduce thepulling force required to interengage the contact surfaces. The spacingbetween the contact surfaces 11a and 15a is limited by means of thecatch 19 which is mounted in the cavities in the knob 15 and insulator16 and which is engaged at its rearwardmost end by the setscrew 20. Withthis structure, rotation of any one of the set screws 20 in theclockwise direction (FIG. 2) causes the contact surface spacing todecrease, and rotation of the setscrew in the counterclockwise directioncauses the contact surface spacing to increase, as long as the spring 23is compressed. Thus, should it become necessary to adjust the airgap 18,for example, to ensure shock resistance when large electrical potentialsare developed, or should it be desirable to adjust the required pullingforce, the setscrews 20,20 and the threaded fastener 26 may be rotatedaccordingly, The knob also has a cover 28 which masks the aforementionedadjusting mechanisms and provides a pleasing appearance for the knobassembly 10.

In the embodiment illustrated in FIGS. 3 and 4, the knob structure 30operates upon forward displacement of the knob 35 on the axis B relativeto the shank 31 to cause the spring between the contact surfaces todecrease and the surfaces to ultimately interengage one another. In thisembodiment, the shank 31 has an arcuate, in the present instance annularcontact surface 31a and the knob 35 has a like contact surface 35a inregistry therewith which tapers to an apex 35b a spaced distancetherefrom. Like the knob assembly 10 of FIG. 1, the FIG. 3 embodimenthas an insulator 36 mounted in the end of the shank 31, and theinsulator 36 has a bore slidably receiving a forwardly protruding stem35' on the knob. In the present instance, the contact apex 35b of theknob 35 is spaced from the shank surface 31a by means of catches 39,39mounted in circumferentially spaced axially extending cavities in theinsulator 36 and in like cavities in the knob 35. A compression spring37 engages between the catch 39 and the bottom of the shank-cavity tourge one end of the catch 39 against a setscrew 40 threadedly engaged ininternal threads in the catchcavity in the knob 35. The spacing andhence the airgap 38 between the apex 35b and the contact surface on theshank l2 limited by means of a bolt 42 threaded into the shank 31 andhaving its head 43 engaging the knob 35. Similarly to the aforedescribedFIG. 1 embodiment, the spacing may be decreased by rotating the bolt 42in the clockwise direction FIG. 4) and the spacing may be increased byrotating the bolt 42 in the counterclockwise direction. If desired, theamount of force required to effect interengagement of the contactsurfaces may be adjusted by rotating the setscrews 40, clockwiserotation increasing the required interengagement force andcounterclockwise rotation decreasing the interengagement force. As inthe FIG. 1 embodiment, a cover 48 on the front of the knob masks theaforementioned adjusting mechanism.

In each of the aforedescribed embodiments, the knobs are insulated fromthe shank so that there is no substantial discharge of staticelectricity when the knob is first grasped. When the knob is thereafteroperated, contact between the members is effected remotely from thepoint where the knob is grasped, so as to avoid discharge in the regionof the hand. The discharge is facilitated by the use of the apex tocooperate with the contacting surface, and this point of discharge isencased within the knob.

The knob assembly 50 illustrated in FIGS. 5 and 6 operates upon rotationof the knob 55 in either the clockwise or counterclockwise direction toeffect interengagement of the contact surfaces. In this embodiment, aninsulator 56 is fixedly secured to the shank 51 and rotatably mounts theknob 55 thereon. The contact surfaces are disposed in a circleconcentric with the axis of rotation C of the knob 55 and interengageone another upon a predetermined amount of rotation of the knob 55relative to the shank 51. In the present instance, the contact surfacesare provided on two pairs of pins 51a, 55a and 51a, 55a which extendalong the axis C on diametrical sides thereof. The pins 51a, 51a arepressed into bores in the shank 51 and extend through the insulator 56to terminate adjacent the inside of the knob 55. The pins 55a, 550 aresimilarly mounted in the knob 55 and terminate adjacent to the insulator56 so that each pair 51a and 55a of the pins is disposed incircumferentially spaced side-by-side relation. The pairs of pins aremaintained in normally spaced relation by means of a resilient memberwhich engages the insulator 56 and the knob 55. In the present instance,as may be seen in FIG. 5, the resilient member is a torsion spring 57having an axially extending arm mounted in the insulator 56 and anotheraxially extending arm mounted in the knob 55. The knob 55 is secured tothe shank 51 by means of a bolt 62 threadedly received in the insulator56 and extending coaxially through the coils of the torsion spring 57with its head engaging the knob 55. Thus, when the knob 55 is rotated inthe clockwise direction (FIG. 6) the spacing between the top pair ofpins decreases to transfer static electricity from the knob 55 to theshank 51, and when the knob 55 is rotated in the counterclockwisedirection, the spacing between the bottom pair of pins decreases totransfer static electricity within the confines of the knob, continuedrotation of the knob in either of the aforementioned directionseffecting interengagement of the surfaces and actuation of the latchingassembly 53. Like the aforedescribed embodiments, a cover 58 is providedon the front of the knob 55.

In accordance with another object of the present invention, apparatusmay be provided for use with conventional doorknobs to effect thedischarge of static electricity from a person when the person reaches tograsp the knob. In the embodiment of FIGS. 7-10 (Sheet 2) staticelectricity is discharged when the doorknob assembly 70 is pushed orturned, and in the embodiment of FIGS. 1113, static electricity isdischarged when the knob assembly 90 is squeezed. As may be seen in FIG.7, the knob assembly 70 comprises a first electrically conductive memberor knob 75 and a second electrically conductive member 76 surroundingthe knob 75. The cover 76 extends across the front of the knob 75 andinwardly toward a shank 71 behind the knob. The cover 76 is spaced fromthe knob by means of insulation 77 which frictionally engages both thecover 76 and the periphery of the knob 75 so that the knob 75 rotateswhen the cover 76 is rotated. In this embodiment, contact surfaces areprovided by means of a series of pins 80,80 carried by the insulator 77in circumferentially spaced relation around the periphery of the knob 75and a pair of tabs 81,81 associated with each pin. Each of the pins 80has its head engaging the knob 75 and its stem projecting radiallyoutward therefrom, and each pair of the tabs 81 is integral with thecover 76, extending inwardly therefrom in registry with opposite sidesof each pin stem 80 b. The insulator 77 is recessed as indicated at 83in the vicinity of the pins and tabs and is resilient so that the tabs81, 81 are normally spaced from the stems of their associated pinswithin the recesses 83 but so that they may be engaged therewith fortransferring static electricity within the confines of the recesses 83when the cover 76 is rotated in either of the clockwise orcounterclockwise directions (See FIG. 9). If desired, a tab 82 may beformed on the cover 76 to project inwardly toward the front of the knob75 for effecting contact when the cover 76 is displaced forwardly towardthe knob with a push type of motion similar to that required to effectinterengagement of the contact surfaces in the FIG. 3 embodiment (SeeFIG. Thus, with this structure, the cover 76 may be mounted on theconventional doorknob to thereby enable a person to discharge staticelectricity by either pushing on the cover or turning the cover ineither the clockwise or counterclockwise directions.

In the embodiment illustrated in FIGS. 11-13, static electricity isdischarged when a squeezing action is applied to the doorknob assembly90. For this purpose a first member, in the present instance a doorknob91 is surrounded by a second member or band 92 which surrounds a majorportion of its periphery. The bank 92 is spaced from the periphery ofthe knob 91 by means of an insulator 93 which covers the front of theknob and which has a pair of upstanding flanges 93a, 93a engagingopposite edges of the band 92 to prevent the band from being displacedaxially relative to the knob 90. In the present instance, the bank 92 isformed of resilient springlike material having a natural radius ofcurvature which is slightly less than the radius of curvature of theouter periphery of the insulator 93. Thus, by virtue of its inherentelasticity, the bank 92 clamps itself onto the insulator 93. In thisembodiment, the contact surfaces include the periphery of the knob 91and a series of tabs 95,95 formed integrally with the band 92 andprojecting inwardly through a like series of recesses or holes 96,96 inthe insulator 93 and toward the periphery of the knob. The insulator 93is sized to frictionally engage the knob 91 and the band 92 to cause theknob 91 to rotate when the band 92 is rotated. In addition, theinsulator is formed of an elastically deformable or compressiblesubstance which enables the tabs 95,95 to be engaged against theperiphery of the knob within the recesses 96 for discharging staticelectricity thereto when the bank 92 is squeezed.

The present invention is also adapted for use in conjunction withmetallic pushbuttons, for example an elevator call button -100(FIG. 14).As may be seen therein, a first member, in the present instance ametallic plate 101 slidably mounts a plunger 102 for displacementtheretoward to effect operation of a switch assembly 103 mounted behindthe plate 101. A cap of second metallic member 104 surrounds theterminus of the plunger 102 and is spaced therefrom by means ofinsulation 105. The cap 104 has a central thumbrest portion 109 and anannular wall 106 which extends along the plunger 102 and toward theplate 101 and which terminates in an apex 106b a spaced distance fromthe plate 101. In this embodiment, the cap 104 is normally biased awayfrom the plate 101 by means of a compression spring 107 which is mountedin the plunger 102. The spacing between the apex and the plate 101 islimited by means of a split washer 108 mounted in a peripheral groove inthe plunger 102 and engageable against the inside of the plate 101. Withthis structure, static electricity may be discharged from a person andthe switch assembly 103 actuated when the person touches the thumbrest109 of the cap 104 and depresses the plunger 102 toward the plate 101 tocause the apex 106b of the annular wall 106 to engage the plate 101. Thepoint of static discharge between the apex 106b and the contact surfaceof the plate 101 is remote from the thumbrest 109.

In a further embodiment, the present invention provides apparatus foruse in conjunction with an electrical toggle switch 200 to enable aperson to discharge static electricity when the switch is actuated. Tothis end, a first member, in the present instance a metallic switchcover plate 201 (FIG. 15, Sheet 3) spans across an opening in a wall 202mounting a box 203 in which is carried a conventional electrical toggleswitch 200. The switch 200 has a handle or operator 204 projectingoutwardly through an elongated slot 205 in the cover plate 201 andoperable between alternate positions adjacent each end of the slot 205.The cover plate 201 is mounted to the box 203 by means of threadedfasteners, in the present instance screws 206, 206 which are threadedinto the conventional sockets of a switch-mounting strap 200 which ismounted on mounting ears 207, 207 of the box 203.

In order to prevent a person from receiving a shock when his finger ispositioned in close proximity to the plate 201 and handle 204, a secondmember or element 210 is mounted on the front of the plate 201 andinsulated spaced distance therefrom. 1n the illustrated embodiment, thesecond member comprises an elongated metal strip having intumed flanges211, 211 through which pass the screws 206, 206. The strip is insulatedfrom the cover plate 201 by means of nonconductive shouldered washers213, 213 (P16. 19) disposed intermediate the plate and one side of theflanges 211, 211 and nonconductive washers 215, 215 disposed between theother side of the flanges 211, 211 and the heads of the screws 206, 206.In the present instance, the entire cover plate 201 is metallic andelectrical communication between the plate and the box 203 is providedby means of metallic washers 217, 217 disposed intermediate the insideof the plate 201 and the lips 207, 207 around the screws 206, 206. Thus,when the screws 206, 206 are rotated, a clamping action occurs betweenthe cover plate 201 and the lips 207, 207 to effect electricalcommunication therebetween.

For the purpose of transferring electrical energy from the element 210to the cover plate 201, contact means, in the present instance tabs 220,220 are provided on the element 210. In the present instance, the tabs220, 220 are formed integrally with the element 210 and protrudetherefrom toward the cover plate 201 adjacent opposite ends of anelongated slot 221 which registers with the slot in the cover plate 201and through which the handle 204 projects. The tabs 220, 220 arenormally spaced and biased away from the cover plate 201 by the loopedshape of the flanges 211, 211 which operate to prevent a persons fingersfrom contacting the screws 206, 206 and thereby being shocked, aspresently would be possible even with conventional cover plates ofnonconductive material such as plastic (See FIG. 17) Each of the tabs220 is provided with an apex to engage the contact surface of the plateremote from the point where the finger rests on the element 210. If theplate is nonconductive, the apex of the tab 220 may be positioned toengage the screw 206. in addition, as may be seen in FIG. 15, theelement 210 is preferably disposed inwardly of the terminus of thehandle 204 so that a person is required to displace the element 210toward the plate and the tabs 220, 220 into contact therewith beforebeing able to flip the handle 204 upwardly or downwardly (See FIG. 17).It is also to be noted that apertures are provided in each end of theelement 210 in registry with the screws 206, 206 to receive ascrewdriver for rotating the screws to mount and dismount the element210.

In view of the foregoing, it should be apparent that novel means has nowbeen provided for enabling a person to periodically discharge staticelectricity while performing routine functions.

While preferred embodiments of the present invention have been describedin detail, various modifications, alterations or changes may be madewithout departing from the spirit and scope of the present invention asdefined in the appended claims.

What is claimed is:

1. Apparatus for transferring an accumulated charge of staticelectricity between a person and an object comprising: firstelectrically conductive member connected to the object and mounted forrotation an an axis, a second electrically conductive member spaced fromsaid first member and mounted for rotation on an axis coaxial therewith,the conductive portion of said second member being exposed forengagement with the person, means providing electrical insulation on oneof said members and an airgap between said first and second members,contact means on said members and carried on at least one of saidmembers and projecting toward the other of said members, said contactmeans including at least one surface carried by each of said members aspaced distance outwardly from said axis, said surfaces confronting oneanother and lying in a circle concentric with said axis and beingnormally disposed in circumferentially spaced relation, and meansbiasing said contact means on one member away from said other member tonormally space said contact therefrom, whereby the spacing between thesurfaces may be diminished when the second member is rotated relative tothe first member and against said biasing means to thereby effect thetransfer of static electricity therebetween.

2. Apparatus according to claim 1 including a latching assemblyconnected to said first member and being operable upon rotation inselected clockwise and counterclockwise directions, means including apair of said surfaces carried by each of said members to limit saidrelative rotation when said second member is rotated in a selected oneof said directions, said biasing means connected to said members tonormally space said confronting surfaces at substantially equaldistances from one another, so that when the second member is rotated inthe clockwise direction, the spacing between the confronting surfacesdecreases to transfer static electricity to the first member andinterengagement of the surfaces causes the first member to rotate foroperating the latching assembly, and when the second member is rotatedin the counterclockwise direction the spacing between the surfacesdecreases to transfer static electricity to the first member andinterengagement of the surfaces causes the first member to rotate foroperating the latching assembly.

3. Apparatus according to claim 1 wherein said first member includes ametallic doorknob, said second member includes a metallic elementsurrounding the periphery of said knob, said insulation means includes aresilient substance having an inwardly facing surface frictionallyengaging the inner periphery of said element, and being elasticallydeformable to provide said biasing means, said contact means comprisingat least one pin engaging the outer periphery of said knob andprojecting radially outward therefrom and at least one inward projectionin said metallic element and depending therefrom toward said pinalongside thereof, whereby the pin is engaged by said projection whenthe metallic element is rotated relative to the knob.

4. Apparatus according to claim 1 wherein said first member includes ametallic knob surrounding the terminal portion of said shank, saidcontact means comprising metallic studs secured to said shankdiametrically with respect to said axis and extending axially towardsaid knob, and metallic studs secured to said knob and extending axiallytoward said shank, said studs normally being disposed in spacedside-by-side relation, said insulation means being secured to said shankand having a cylindrical outer periphery rotatably receiving said knob,said biasing means including a torsion spring having one arm engaging insaid insulation means and another arm engaging in said knob, andincluding a threaded fastener threadedly engaging said insulation meanson said axis and engaging said knob to rotatably mount said knobadjacent said shank, whereby the studs are operatively engaged uponrotation of the knob in either the clockwise or counterclockwisedirection.

5. Apparatus for transferring an accumulated charge or staticelectricity between a person and an object comprising a firstelectrically conductive member connected to the object, a latchingassembly connected to said first member and being operable upon rotationof said first member on an axis, a second electrically conductive memberspaced from said first member, means slidably mounting said secondmember to said first member for displacement on said axis, meansproviding electrical insulation on one of said members and an airgapbetween said members, contact means on each of said members disposed inaxially spaced confronting relation, means biasing said contact means onone member away from said other member to normally space said contactmeans from one another, means acting counter to said biasing means forlimiting the spacing between said contact means and other means to limitrelative angular displacement between said members, so that relativeaxial displacement between the members decreases the spacing between thecontact means for transferring electrical energy and rotation of thesecond member on its axis causes said other means to actuate thelatching assembly.

6. Apparatus according to claim 5 wherein said other means includes atleast one axially extending cavity spaced outwardly from said axis inone of said members, another axially extending cavity in registry withsaid one cavity in the other of said members, and. a catch slidablyreceived in said cavities, whereby the interengagement of the catch inthe cavities operates to couple the members and prevent relative angulardisplacement therebetween while permitting axial displacement.

7. Apparatus according to claim 6 wherein said first member includes adoorknob shank and said second member includes a doorknob surroundingthe terminal portion of said shank, said insulation means including aninsulator mounted in the end of said shank, a stem on said knob slidablein said insulator, said stem having a through bore therein, and saidspacing-limiting means including a bolt extending through said bore withits head engaging said knob and its tail carried by said insulator,whereby displacement of the knob axially of said bolt decreases thespacing of the contact means.

8. Apparatus according to claim 7 including an outwardly projectingportion on said shank defining one arcuate surface and an inwardlyprojecting portion on said knob defining another arcuate surfaceconfronting said shank portion, the arcuate surface on said knob portionhaving a tapered apex adjacent said shank portion and being engageabletherewith upon axial displacement of said knob, said biasing meansincluding a shoulder in said stem-bore and a compression springsurrounding said bolt and seated between said shoulder and saidbolt-head to bias said knob axially toward said shank.

9. Apparatus according to claim wherein said contact means includesconfronting arcuate surfaces with one surface having a tapered portionterminating in an apex adjacent another arcuate surface, said biasingmeans including a compression spring mounted in one of the cavities toengage the 10. Apparatus for transferring an accumulated charge ofstatic electricity between a person and an object comprising: a firstelectrically conductive member connected to the object, said firstmember including a metallic plate, a plunger slidably mounted in saidplate, a second member including a metallic cap mounted on andsurrounding said plunger on the end thereof remote from said plate,insulation mea'ns interposed between said cap and said plunger, said caphaving a surface spaced from and confronting said plate to providecontact means, means connected to said plunger to bias said plunger andhence said surface away from said plate, whereby the accumulated staticelectricity is transferred from the cap to the plate when the plunger isdisplaced toward the plate and the spacing between the surface on thecap and the plate is decreased.

11. Apparatus for transferring an accumulated charge of staticelectricity between a person and an object comprising: a firstelectrically conductive member connected to the object and a secondelectrically conductive member spaced from said first member, a coverdisposed intermediate said first and second members and having anelongated slot, an operator protruding forwardly through said slot andoperable from in front of said cover between alternate positionsadjacent opposite ends of said slot, means adjacent said opposite endsof said slot providing electrical communication between said front ofthe cover and said first member located behind said cover, the secondmember including a metallic element having an elongated aperture inregistry with said slot and being disposed inwardly of the outermostterminus of said operator, contact means including a tab on the back ofsaid element normally spaced from said electrical communication meansand operable upon rearward displacement to establish electricalconnection with said electrical communication means, and means includingbiasing means to mount said element for rearward displacement wherebyelectrical energy is transferred from the element to the first memberbehind the cover when the element is displaced by the person actuatingsaid operator.

12. Apparatus according to claim 11 and further including an additionaltab on saidelement and wherein said electrical communication meansincludes metallic portions on said cover in electrical communicationwith said first member, said biasing means including a resilient intumedflange on said element adjacent opposite ends of said aperture, saidelement mounting means including an opening in each flange and athreaded fastener extending through each opening and threadedly receivedin said one member, and insulation means including nonconductive washersbetween the metallic portions of said cover and the flanges andnonconductive washers and between the heads of the threaded fastenersand the flanges, so that the tabs are normally spaced from the cover bythe resiliency of the flanges.

13. Apparatus according to claim 12 and further including an electricalmounting box and wherein said first member includes a strap mountingsaid box with said operator and confronting the back of the cover, saidstrap threadedly receiving said threaded fasteners, said element beingmetallic with said tabs being formed integrally therewith, and includingelectrically conductive washers disposed intermediate said cover and thestrap around the threaded fasteners, so that rotation of the fastenerscauses a clamping action to effect electrical communication between thecover and the mounting box.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. DatedNovember 16 1971 Inventor (8) S tanley Backer It is certified that errorappears in the above-identified patent and that said Letters Patent arehereby corrected as shown below:

Col. 2, line 65 "60" should be 50" C01. 3, line 39 "bank should be"band" Col. 6, line 9 DITTO Cole 6, line 4 Col. 6, line 30 Col. 4, line52 "shank 12" should be "shank is" Col. 6, line 37 "of", firstoccurrence, should be or 7, li 59 "an", first occurrence should be onC01. 7, line 73 after "Contact" the word "means" omitted Col. 8, line 36the following omitted after "metallic" and up to "knob" "shank having aterminal portion, said second member includes a metallic" Col. 8, line53 "or" should be "of Col. 9, line 28 should be "according to claim 7"Signed and sealed this 6th day of June 1972.

(SEAL) Attest:

EDWARD M.FLETCHL+1R, JR. ROBERT GO'F'TSCHALK Attesting OfficerCommissioner of Patents )RM PC4050 (10-69) uscoMM-Dc 60376-P69 I7 U 5GOVERNMENT PRINTINIS (JFFICl Nil! U356 )34

1. Apparatus for transferring an accumulated charge of staticelectricity between a person and an object comprising: firstelectrically conductive member connected to the object and mounted forrotation an an axis, a second electrically conductive member spaced fromsaid first member and mounted for rotation on an axis coaxial therewith,the conductive portion of said second member being exposed forengagement with the person, means providing electrical insulation on oneof said members and an airgap between said first and second members,contact means on said members and carried on at least one of saidmembers and projecting toward the other of said members, said contactmeans including at least one surface carried by each of said members aspaced distance outwardly from said axis, said surfaces confronting oneanother and lying in a circle concentric with said axis and beingnormally disposed in circumferentially spaced relation, and meansbiasing said contact means on one member away from said other member tonormally space said contact therefrom, whereby the spacing between thesurfaces may be diminished when the second member is rotated relative tothe first member and against said biasing means to thereby effect thetransfer of static electricity therebetween.
 2. Apparatus according toclaim 1 including a latching assembly connected to said first member andbeing operable upon rotation in selected clockwise and counterclockwisedirections, means including a pair of said surfaces carried by each ofsaid members to limit said relative rotation when said second member isrotated in a selected one of said directions, said biasing meansconnected to said members to normally space said confronting surfaces atsubstantially equal distances from one anotheR, so that when the secondmember is rotated in the clockwise direction, the spacing between theconfronting surfaces decreases to transfer static electricity to thefirst member and interengagement of the surfaces causes the first memberto rotate for operating the latching assembly, and when the secondmember is rotated in the counterclockwise direction the spacing betweenthe surfaces decreases to transfer static electricity to the firstmember and interengagement of the surfaces causes the first member torotate for operating the latching assembly.
 3. Apparatus according toclaim 1 wherein said first member includes a metallic doorknob, saidsecond member includes a metallic element surrounding the periphery ofsaid knob, said insulation means includes a resilient substance havingan inwardly facing surface frictionally engaging the inner periphery ofsaid element, and being elastically deformable to provide said biasingmeans, said contact means comprising at least one pin engaging the outerperiphery of said knob and projecting radially outward therefrom and atleast one inward projection in said metallic element and dependingtherefrom toward said pin alongside thereof, whereby the pin is engagedby said projection when the metallic element is rotated relative to theknob.
 4. Apparatus according to claim 1 wherein said first memberincludes a metallic knob surrounding the terminal portion of said shank,said contact means comprising metallic studs secured to said shankdiametrically with respect to said axis and extending axially towardsaid knob, and metallic studs secured to said knob and extending axiallytoward said shank, said studs normally being disposed in spacedside-by-side relation, said insulation means being secured to said shankand having a cylindrical outer periphery rotatably receiving said knob,said biasing means including a torsion spring having one arm engaging insaid insulation means and another arm engaging in said knob, andincluding a threaded fastener threadedly engaging said insulation meanson said axis and engaging said knob to rotatably mount said knobadjacent said shank, whereby the studs are operatively engaged uponrotation of the knob in either the clockwise or counterclockwisedirection.
 5. Apparatus for transferring an accumulated charge or staticelectricity between a person and an object comprising a firstelectrically conductive member connected to the object, a latchingassembly connected to said first member and being operable upon rotationof said first member on an axis, a second electrically conductive memberspaced from said first member, means slidably mounting said secondmember to said first member for displacement on said axis, meansproviding electrical insulation on one of said members and an airgapbetween said members, contact means on each of said members disposed inaxially spaced confronting relation, means biasing said contact means onone member away from said other member to normally space said contactmeans from one another, means acting counter to said biasing means forlimiting the spacing between said contact means and other means to limitrelative angular displacement between said members, so that relativeaxial displacement between the members decreases the spacing between thecontact means for transferring electrical energy and rotation of thesecond member on its axis causes said other means to actuate thelatching assembly.
 6. Apparatus according to claim 5 wherein said othermeans includes at least one axially extending cavity spaced outwardlyfrom said axis in one of said members, another axially extending cavityin registry with said one cavity in the other of said members, and acatch slidably received in said cavities, whereby the interengagement ofthe catch in the cavities operates to couple the members and preventrelative angular displacement therebetween while permitting axialdisplacement.
 7. Apparatus according to claim 6 wherein said firstmember includes a doorknob shank and saId second member includes adoorknob surrounding the terminal portion of said shank, said insulationmeans including an insulator mounted in the end of said shank, a stem onsaid knob slidable in said insulator, said stem having a through boretherein, and said spacing-limiting means including a bolt extendingthrough said bore with its head engaging said knob and its tail carriedby said insulator, whereby displacement of the knob axially of said boltdecreases the spacing of the contact means.
 8. Apparatus according toclaim 7 including an outwardly projecting portion on said shank definingone arcuate surface and an inwardly projecting portion on said knobdefining another arcuate surface confronting said shank portion, thearcuate surface on said knob portion having a tapered apex adjacent saidshank portion and being engageable therewith upon axial displacement ofsaid knob, said biasing means including a shoulder in said stem-bore anda compression spring surrounding said bolt and seated between saidshoulder and said bolt-head to bias said knob axially toward said shank.9. Apparatus according to claim wherein said contact means includesconfronting arcuate surfaces with one surface having a tapered portionterminating in an apex adjacent another arcuate surface, said biasingmeans including a compression spring mounted in one of the cavities toengage the catch and urge it outwardly thereof and bias said knoboutwardly from said shank.
 10. Apparatus for transferring an accumulatedcharge of static electricity between a person and an object comprising:a first electrically conductive member connected to the object, saidfirst member including a metallic plate, a plunger slidably mounted insaid plate, a second member including a metallic cap mounted on andsurrounding said plunger on the end thereof remote from said plate,insulation means interposed between said cap and said plunger, said caphaving a surface spaced from and confronting said plate to providecontact means, means connected to said plunger to bias said plunger andhence said surface away from said plate, whereby the accumulated staticelectricity is transferred from the cap to the plate when the plunger isdisplaced toward the plate and the spacing between the surface on thecap and the plate is decreased.
 11. Apparatus for transferring anaccumulated charge of static electricity between a person and an objectcomprising: a first electrically conductive member connected to theobject and a second electrically conductive member spaced from saidfirst member, a cover disposed intermediate said first and secondmembers and having an elongated slot, an operator protruding forwardlythrough said slot and operable from in front of said cover betweenalternate positions adjacent opposite ends of said slot, means adjacentsaid opposite ends of said slot providing electrical communicationbetween said front of the cover and said first member located behindsaid cover, the second member including a metallic element having anelongated aperture in registry with said slot and being disposedinwardly of the outermost terminus of said operator, contact meansincluding a tab on the back of said element normally spaced from saidelectrical communication means and operable upon rearward displacementto establish electrical connection with said electrical communicationmeans, and means including biasing means to mount said element forrearward displacement whereby electrical energy is transferred from theelement to the first member behind the cover when the element isdisplaced by the person actuating said operator.
 12. Apparatus accordingto claim 11 and further including an additional tab on said element andwherein said electrical communication means includes metallic portionson said cover in electrical communication with said first member, saidbiasing means including a resilient inturned flange on said elementadjacent opposite ends of said aperture, said element mounting meansincluding an opening in each flange and a threaded fastener extendingthrough each opening and threadedly received in said one member, andinsulation means including nonconductive washers between the metallicportions of said cover and the flanges and nonconductive washers andbetween the heads of the threaded fasteners and the flanges, so that thetabs are normally spaced from the cover by the resiliency of theflanges.
 13. Apparatus according to claim 12 and further including anelectrical mounting box and wherein said first member includes a strapmounting said box with said operator and confronting the back of thecover, said strap threadedly receiving said threaded fasteners, saidelement being metallic with said tabs being formed integrally therewith,and including electrically conductive washers disposed intermediate saidcover and the strap around the threaded fasteners, so that rotation ofthe fasteners causes a clamping action to effect electricalcommunication between the cover and the mounting box.